regex - (vim) regex: masking text with help of pattern

Question

Am i correct to understand, that the definition

:range s[ubstitute]/pattern/string/cgiI

suggests that in the string part indeed only strings are to be used, that is patterns not allowed? What i would like to do is do replacement of say any N symbols at position M with X*N symbols, so i would have liked to use something like this:

:%s/^\(.\{10}\).\{28}/\1X\{28}/g

Which does not work because \{28} is interpreted literally.

Is writing the 28 XXXXX...X in the replace part the only possibility?

Answer 1

替换部分中唯一允许的正则表达式构造是编号组：\1 \2 \3 等。重复构造{28}在那里无效，尽管这是一个聪明的主意。您必须使用 28 个 X。

Answer 2

您可以通过在替换部分中使用表达式\=。您必须通过 访问匹配项submatch()，并将其与静态字符串连接在一起，您可以通过以下方式生成该字符串repeat()：

:%s/^\(.\{10}\).\{28}/\=submatch(1) . repeat('X',28)/g

Answer 3

另一种选择是在替换部分中使用表达式：

:%s/^\(.\{10}\).\{28}/\=submatch(1).repeat("X",28)/g

第一个匹配组是用 获得的submatch(1)。有关详细信息，请参阅:h sub-replace-expression。